Electric-arc lamp



(No Model.)

S. E. NUTTING.

ELECTRIC ARG LAMP.

No. 542,490. Patented July 9, 1895.

parts.

UNITED STATES PATENT OEEICE.

SAMUEL E. NUTTING,OE OAK PARK, ASSIGNOR TO GEORGE W. FURBECK AND JOSEPHKETTLESTRINGS, OF CHICAGO, ILLINOIS.

ELECTRIC-ARC LAMP.

SPECIFICATION forming part of Letters Patent No. 542,490, dated July 9,1895.

Application tiled September S, 1894. Serial No. 522,413. (No model.)

To @ZZ whom it may concern:

Be it known that l, SAMUEL E. NUTTING, a citizen of the United States,residing at Oak Park, county of Cook, State of Illinois, have invented anew Improvement in Arc Lamps; and I declare the following to be afull,clear, and concise description of the same.

My invention relates to arc lamps wherein the feed of the cai-bons iscontrolled by the action produced by the expansibleness of certain partsdue to heat caused by the resistance to the current of electricitypassing through that portion of the circuit. I dispense with theelectromagnets and dash-pots ordinarily used, thereby greatlysimplifying,7` the device, cheapening the construction, and greatlyimproving the efficiency of carb'onfeeding mechanism. y

Referring to the drawings, Figure lis a side elevation of the mainportion of an arc lamp embodying my invention, the top plate being insection in order to disclose the operative Fig. 2 is a bottom plan viewof the iop plate, taken on the line 2 2, Fig. l. Fig. 3 is a viewtransverse to Fig. l and having the lower part of the lamp cut away.

Similar letters refer to like parts throughout the specification anddrawings.

A is the top plate of an arc lamp Depending from A and secured insuitable lugs are the side rods B. Secured upon the side rods B at alittle distance below the top plateA is a circular plate C. Dependingfrom the circular plate C and between the side rods B are the insulatedsupplemental guide-rods D, having mounted thereon the carbon-carryingracks E E', said racks consisting of tubes telescoping the guide-rods D,and having secured thereon the cross-bars E, adapted to hold thecarbons. The top plate A is provided with suitable binding-posts A A2.Passing downwardly from the binding-post A through the plate C to thecarbon-carrying rack E is the flexible conductor F, secured at its lowerend to the rack E by means of the screw E. Connecting the binding-postA2 to the insulated eross-head G is a connector G. Placed opposite theinsulated cross-'head Gis asimilar cross-head H. The cross-heads G Ilare secured to and insulated from the top plate A. Passing from thecross-head G to the crosshead H are a number of small wi res I,consisting ot one wire passed back and forth about the small screws l,secured in the cross-heads G H. In order to securea proper tension tothe wires I, I have provided theinwardly-extending portions of thecross-heads G H with setscrews G2 H3, said screws being adapted to tiltthe cross-heads G H, so as to increase the distance between the pointsof attachment ofthe wires I to the cross-heads G H, thus tightening thewires. Secured to the cross-head I-I by means of the screw H is anotherflexible conductor J, said conductor passing downwardly through thecircular plate C to the upper-carbon rack E', to which it is attached.

Pivoted between the depending lugs K of the plate K', secured on theunder side of the top plate A, is a lever L. Pivotally mounted upon andabout midway of the lever L is an insulated bridge L', upon which thecrosswires I rest. Inter-posed between the top plateA and the lever L,near its outer end, is a distended coil-spring L2, said spring tendingat all times to raise the lever L, thus keeping the bridge L in closecontact with the cross-wires I.

Mounted in suitable standards M upon the circular plate C is the shaftN, having secured thereon the brakewheel N', provided on either sidewith the drums N2 N5, upon which are oppositely Wound the dependingcords or chains O O', said cords or chains being secured at their lowerends to the carbon-racks E E', respectively. Pivoted upon the shaft N isthe stirrup P, said stirrup having the brake Q piyoted therein, saidbrake adapted to engage the periphery ofthe brake-wheel N.

Connecting the outwardly-extending arm Q of the brake Q to the lever Lis a link R, said link being provided with aseries of holes whereby aproper adjustment is secured. Theouter end or loop portion of thestirrup P is provided with a weight P'. This weight is designed toinsure the release of the brake from contact with the brake-wheel N. In

order to properly adjust the brake Q, I have provided the stop S,extending upwardly from the circular plate C and having the checknut S'thereon to secure the stop against movement when properly adjusted.

By reference to Figs. l to 3 it will be seen IOS that the stop S comesin contact with a forwardly-extending arm Q2 of the brake Q.

The operation of my invention will be readily understood.

It will be seen that the current of electricity entering thebinding-post A will pass downwardly through the iiexible conductor F tothe carbon-rack E, thence into the lower carbon, thence through thevoltaic arc to the upper carbon and rack E', thence upwardly by means ofthe iiexible conductor .I to the cross-head l-l, thence through thewires I to the cross-head G, and finally to the binding-post A2 throughthe connector G. The current in passing through the wires I, meetingrmore or less resistance, produces sucient heat to expand the wires, theamount of said expansion being due to the strength of the currentpassing through the circuit. By reference to Figs. l to 3 it will beseen that as the wires I expand the lever L will be raised by thecontraction of the spring Linterposed between the lever L and top plateA. Interposed between the leverLand the wires I is a bridge L',pivotally mounted to the lever L, in order that it may be automaticallyadjustable to the difference in the expansiveness of the wires. A smallgage of Wire is used because of its sensitiveness to variations oftemperature, thus securingto the leverL and connected parts a delicateand quick action. v

My purpose in employing several parallel wires of small diameter andconsiderable length is to insure an almost instantaneous'action of thefeed mechanism, for itwillbe seen that six small wires will expandapproximately six times as rapidly as one wire equal in size to the sixsmall ones.

I do not wish it to be understood that I confine myself to a number ofwires, as shown, but might employ a metallic ribbon to connect the fixedcross-heads and carry the current of the circuit of the lamp.

By reference to Fig. l of the drawings it will be seen that the outerend of the lever L is connected to the rearwardly-extending arm Q of thebrake Q by a link R, adapted to rock the brake Q on its bearings in thestirrup P until said brake contacts with the periphery of thebrake-wheel, when further upward motion of the lever L and connectingparts will cause the brake-wheel N to rotate upon its axis and impart acorresponding motion to the drums N2 N3, which in turn will separate thecarbons by actuating the carbonracks through the winding of the cords orchains O O upon the drums N2 N3.

When a perfect arc is secured, the wires I cease to expand, owing to adecrease in the heat due to a less current traversing the circuit.

In order to prevent overheating of the wires I, I have provided ashort-circuiting device H', consisting of a suitable conductor securedat one end of the cross-head G and so adjusted that when the lever L hasmoved upwardly a certain distance it will cause the opposite end of theconductor H to contact with the crosshead H and thus shorten the circuitand thereby relieve the wires I of excessive current, yet in no wiseinterfering with or reducing the current supplied to the carbons.

External atmospheric temperatures willv havelittle effect upon the WiresI, owing to the fact that the cross-heads G H, to which the wires aresecured, are attached to the metal top plate A, which would be affectedby any variation or change that might atfect the wires. For example, ifa lamp embodying the abovedescribed construction be carried from a warmroom into a refrigerator the metal of the top plate A will contractnearly if not quite as much as the wires I, thus preserving nearly vthesame relation of parts under any or all conditions.

Having thus fully described my invention, what I claim as new, anddesire to secure by Letters Patent, is-

l. An arc lamp, having a carbon-controlling mechanism, consisting of anelectrical conductor secured directly between fixed crossheads, saidconductor and said cross-heads suitably placed in the circuit of saidlamp, means for stretching or tightening said conductor, and a movablepart adapted to bear directly against said conductor all substantiallyas set forth and sli'own.

2. An arc lamp having a carbon controlling mechanism consisting of anumber of small parallel wires secured to fixed cross-heads and placedin the circuit of said lamp, said Wires adapted to expand andcontract'by the action of the temperature resultant upon the resistanceto the current in passing through said wires, a lever placedtransversely to said wires, said lever adapted to bear against saidwires midway between the points of attachment of the Wires to the fixedcross-heads, said lever also adapted to'respond to any action of thewires due to expansion or contraction, and a suitable carbon actuatingmechanism, all substantially as set forth.

3. An arc lamp, having a carbon controlling mechanism consisting of asuitable conductor secured at either end to fixed cross-heads and placedin the circuit of said lamp, and a carbon actuating mechanism consistingof a spring actuated lever suitably connected to the brake and brakeWheel and relative parts, said lever adapted to bear centrally againstsaid conductor and its part to be actuated thereby, all substantially asand for the purpose set forth.

4. In an arc lamp, a short circuiting device placed between xed crossheads connected by a thermo electric conductor, said short circuitingdevice adapted to automatically close and relieve said conductor ofexcessive current, all substantially as set forth.

SAMUEL E. NUTTING. Vtitnesses:

J o. KETTLESTRINGS, D. G. BUTTS.

IOO

